土地承载力两大法则及其适用性

目的]以往的土地承载力研究隐含着限制因素决定论和多因素综合论两大认识倾向。在分析这两大类研究方法论的基础上,提出土地承载力第一、第二法则,以丰富承载力理论体系,为其更好地服务社会实践提供理论依据。方法]采用文献分析法、比较分析法开展研究。结果]沿袭"最小法则"、"限制因子定律"及"木桶原理",土地承载力第一法则揭示的是在一个相对封闭环境的人地系统中,限制性因素对土地承载力的大小往往起决定性作用;该法则通常适用于"地球可以承载多少人口规模?","一个国家能够养活多少人?"及"特殊地区紧缺资源的支撑能力是多少?"等情境。在整体论、系统论思想指导下,土地承载力第二法则昭示的则是在一个相对开放环境的人地系统中,土地承载能力由多种因素共同决定;该法则主要适用于"区域土地综合承载能力"和"区域土地综合承载力指数"两类情境。结论]两大法则下的承载力内涵不同,适用的情景状况理应不同,所服务的研究目标也不尽相同。今后在应用土地承载力两大法则时,除需符合特定的假设条件之余,还应就土地承载力两大法则所蕴含的最值属性、空间尺度与两大法则的关联性等问题做出相关控探索。

Two Laws of Land Carrying Capacity and Applications

Objective] Two cognitive tendencies were implied in the study of land carrying capacity(LCC), they are, the limiting factor theory and the multifactor comprehensive theory. Based on the methodology review of these two types of research, two laws of LCC were refined, which could enrich the theoretical system of carrying capacity and serve the social practice better.Methods] Methods of documentation and comparative analysis were employed.Results] In the lights of the ideas of "the Law of the Minimum", "the Principle of Limiting Factors" and "the Cask Theory", we presented the first law of LCC, which reveals the fact that in a relatively closed man-nature system, the LCC depends on the carrying capacity of the limiting factor exclusively. This law is mainly applied to such situations as "How many people can the Earth carry?", "How many people can a country support?" or "What is the supporting capacity of scarce resources in a particular region?". Under the guidance of holism and systematology, the second law of LCC says that in an absolute open man-nature system, the LCC is determined by the synthesizing effect of multiple factors. Situations like "the amount of regional comprehensive carrying capacity" and "the index of regional comprehensive carrying capacity" can adopt this theorem.Conclusion] Each law explains different connotations of LCC, which means the laws are appropriate for various circumstances respectively, and can meet different research purposes. When applying the two laws of LCC later, such problems as the maximum attribute contained in the LCC, or the relationship between the spatial scale and the laws need to be studied in addition to the prerequisites.